yeselk;
Good afternoon, I hope that the day's as nice and bright in your part of the world as it is here today and that all in your world are well.
At one point in my working life I managed an auto detailing shop and one of the services we performed was freshening up plastic headlights.
When I left that work for my first crack at retirement, I bought a small air powered orbital sander and the pro grade cut polishes and finish coats to do it for friends and family.
Depending upon the age of the vehicle, the make and your sun conditions, it'll usually last for at least a year, sometimes more - again depending upon the same conditions.
If you don't put a UV resistant top wax coating on, it won't last as long in my experience.
I've seen YouTube videos where the restoration shop used a clear UV resistant plastic paint and if you can find some - I can't locally - it might be worth trying too, but I'm not certain.
As mentioned by other previous posters, new lights will give you a fresh start, just shop around a bit and find some OEM quality ones as there is definitely a difference in parts suppliers. I'd suggest asking a body shop you trust whose headlights they prefer. The body shop our detail department was attached to definitely had preferences depending upon the type of vehicle they were going into.
Hopefully that made sense and was useful sir. All the best and good luck with the project.
Dwayne
